Sergeant Stacker
From Halopedia, the Halo wiki
Summary
Sergeant Stacker was one of the Marine leaders to survive the Pillar of Autumn's evacuation. Once on Installation 04, he helped rally the Marines he could find, and helped reestablish the command chain. Unfortunately, he was killed when the Halo was destroyed. He is currently listed as KIA. He was the other "sergeant" figure in the story, often referred to as "the white sergeant" as opposed to Sergeant Johnson.
He is best distinguished in the game by his signature Marine Corps baseball cap as well as the scar across his right eye. He is responsible for a plethora of quotes, including "Triggers down men, triggers down!"
He assists you in the levels Halo, The Silent Cartographer, and Assault on the Control Room.
